Iron deficiency and iron deficiency anaemia remain prevalent in Australia. The groups at highest risk are pre-menopausal women, socially disadvantaged people and those of Indigenous background. Diagnosing iron deficiency using a full blood examination and iron studies can be difficult and can be further complicated by concomitant inflammation. Results of iron studies should always be interpreted as an overall picture rather than focusing on individual parameters. In difficult clinical scenarios, soluble transferrin receptor assays can be useful. Management of iron deficiency involves identification and treatment of the cause of iron deficiency, as well as effective iron replacement. Clinicians should always take a detailed history and perform a comprehensive physical examination of a patient with iron deficiency. Patients should be monitored even if a likely cause of iron deficiency is identified. Patients who fail to respond to iron replacement or maintain iron status should be referred for further investigation, including endoscopy to exclude internal bleeding. Both enteral and parenteral iron are effective at replacing iron. For most adult patients, we recommend trialling daily oral iron (30-100 mg of elemental iron) as the first-line therapy. Safety and efficacy of intravenous iron infusions have improved with the availability of a newer formulation, ferric carboxymaltose. Patients who fail to respond to oral iron replacement can be safely managed with intravenous iron. Blood transfusion for iron deficiency anaemia should be reserved for life-threatening situations and should always be followed by appropriate iron replacement.